How to Make the Lanczos Algorithm Converge Slowly
نویسندگان
چکیده
The Paige style Lanczos algorithm is an iterative method for finding a few eigenvalues of large sparse symmetric matrices. Some beautiful relationships among the elements of the eigenvectors of a symmetric tridiagonal matrix are used to derive a perverse starting vector which delays convergence as long as possible. Why i such slow convergence is never seen in practice is also examined.
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